ronald reagan -- >> oh, now, you're jack kennedy. >> reporter: barb after barb. >> i know you're under a lot of duress to make up for lost ground. but i think people will be better served if we don't keep interrupting each other. >> well, don't take all of the four minutes then. >> reporter: biden was often dominant. maybe a little too dominant. republicans claimed he interrupted ryan 82 times. often breaking out in laughter. even when ryan was talking about iranian nukes. >> and all i have to point to -- >> reporter: biden was even all smiles when he accused ryan of basically not telling the truth. >> this is a bunch of stuff. look, here's the deal. >> what does that mean, a bunch of stuff? >> well, it means it's simply inaccurate. >> it's irish. >> it is. we irish call it malarkey. >> reporter: they disagreed on virtually everything. from syria, to medicare. >> now they got a new plan. trust me. it's not going to cost you any more. folks, follow your instincts on this one. >> they got caught with their hands in the cookie jar, turning medicare into a piggy bank for obama care. >> rep